In this paper, a parameter-free procedure applicable to the detection of a signal in some element of a multiple-resolution- element radar is described. The procedure is based on parameter- free statistics obtained from the generalized maximum likelihood ratio and allows one to eliminate the unknown parameters from the problem. This procedure can be employed whenever the parameters of the distribution of the signal data and no-signal data are unknown. It allows one to find an adaptive test that adjusts itself to the level of the recent clutter and to improve target detectability over various clutter, such as ground, sea and weather clutter. One advantage of the adaptive test is that, over a wide class of no-signal environments, the false alarm rate remains the same. In other words, the adaptive test is able to achieve a fixed probability of a false alarm, which is invariant to intensity changes in the noise background. Also, no learning process is necessary in order to achieve the constant false alarm rate.